Larxene is quite a character, being a part of the organisation XIII Has it's ups and downs of course, but she never truly was fully invested in spreading darkness and soullessness to other Disney worlds and the multiverse that Yensid alongside Mickey and others possess in large, especially confronting the keyblade masters all the time, she had her own interests as far as organisation's foundation. Because in her books, she has been documenting on a phenomenon only known by few and being concealed for the longest time in history, data management. At large, it's a concert that the Disney universe at large, alongside it's subsidiaries and divisions is nothing more than a collection of data and if you can get to the storage and simply mess it up a bit, you would achieve such power, that surpasses any being of darkness or any keyblade user. Sadly for her, meddling with data proved very difficult and unstable, since it has altered her body in return for more power. How did this happen? One time, as Larxene conducted her going out to the furthest and deepest corners of the Disney universe, even more obscure than their classic filmography, it became apparent, that she was sensing a source of unstable mana and that mana was one of many data storages. Since it was so far away, it was a dangerous idea to take hold of it, but she did it anyway and payed big, since data absorbed right into her body, completely bloating her frame outward, making her waistline much bigger in only a couple of seconds, but Larxene didn't feel any regret at her choices, since she later found out that controlling and absorbing data is the only way a user could use it effectively, so as such, she became proud of her new curvature and excess plumpness, to the point of relishing in it so much, that even Xehanort was shocked with her behaviour, but he couldn't find out why she was behaving like this. And as such, Larxene was largely on her own, partying ways with the organisation XIII.

You on the other hand, would join it soon enough as Larxene's replacement and would also discover about the mythical data storage empowerment that Larxene used, but in order to get your answers, you needed to venture far across the Disney realms and find her to talk about it in detail. You ventured forth, not stating about your plans to Xehanort and quickly caught up to Larxene, she was relaxing in the jungles, where Tarzan used to swing across the Amazon river, until he was promptly assigned alongside keybladers to fight darkness, hence the place was a bit empty. Soon enough, Larxene felt your presence and turned to face you, her form expanded and round, soft flesh and power circulating within, the data storage may did damage her figure, but her stance was confident and strong, just as much as her newly provocative outfit, allowing her gut to be in full view, not even ashamed of its enormity. Larxene would speak soon enough.

Another Xehanort dog having shady plans of own egh? Consider yourself lucky, I'm not going to kill you on the spot, unless you want to. Anyway, state your purpose?

Larxene sounded defensive somewhat, but it shouldn't be that hard to explain everything in detail, especially since nothing is more complicated than the plot of the kingdom hearts franchise at large.

Will you do it? Only mind matters.